IGBT with Oil Extraction

As the petroleum industry matures, it must locate and extract oil from deeper and deeper reservoirs under the surface of the earth. The extraction of oil from deep underground, using oil wells is difficult due to high viscosity and inclusion of asphalt. The viscosity can be reduced by either irrigating with hot water, addition of chemicals, or by electric heating of the pipelines. Electric heating technology is widely used by the oil industry because of its low cost. A single phase AC source at 40-100 Hz is supplied to the well wall to provide resistive heating. A basic set up is needed for heating the oil pipe. The heating loop consists of the oil pipe and heater at the bottom of the well. When current flows through the loop, it not only increases the temperature at the bottom of the well but along the pipe due to the resistance of its walls.

For an example, we can say that a 50-Hz, 380-V, three-phase, AC power is converted to a DC bus by the rectifier stage and then inverted using the IGBTs to variable frequency ranging from 40-100 Hz. The heating efficiency is increased by 50 percent with this approach. The set has advantages of small volume and light weight because of using IGBT in the inverter system.